"Cytotoxicity and immunomodulatory activity of Crotoxin isolated from Crotalus Durissus Terrificus adsorbed to silica nanoparticles"

FLORENCIA S. CONTI; EXEQUIEL GIORGI; MARIA EUGENIA DIAZ; MAURICIO DE MARZI; JUAN PABLO RODRÍGUEZ; FEDERICO G. BAUDOU

Mar del Plata

Congreso; Reunión Anual de Sociedades de Biociencia 2023; 2023

Reunion conjunta: SAIC, SAB, AAFE, AACYTAL

In Argentina, snakes from the Viperidae family cause most accidents and so far the only medical treatment approved is serotherapy with antivenoms (AV). Particularly, Crotalus durissus terrificus(rattlesnake) has a neurotoxic venom (V) whose main component is Crotoxin (CTX) responsible for its high lethality. This toxin has immunosuppressive properties that hinder the production processof its AV. In addition, the use of nanoparticles (NP) opened a range of possibilities within the medical field given its properties. Thus, the possibility of using NP, with V toxins, would allow modifying its biological properties in order to use them in the production of new AV.In this work, we isolated CTX by fast protein liquid chromatography (FPLC) and generate nanovenoms (NVs), complexes formed by CTX adsorbed to silica nanoparticles (SiNPs) of different sizes (150 and 330nm). For this, 1 mg/ml of CTX was mixed under stirring with 10 mg of SiNPs (+/-). By Transmission Electron Microscope (TEM) NVs were microphotographed and revealed CTX’s presence in them. The protein profile of whole V, isolated CTX and CTX adsorbed to SiNPs was studied by SDS-PAGE (14%), showing CTX subunits bands post-NVs desorption. The enzymatic activity exerted by CTX of the NVs was studied by hemolysis radial test, and it was found that NVs retain their enzymatic activity (42.57 ± 3.18% NV+, 41.65 ± 3.89% NV-). In addition, some biological properties of these NVs were studied such as their cytotoxicity (MTT cell test over THP-1 cells), in which no significant differences between the NVs and the whole V and CTX were seen. The immunomodulatory activity (cytokines by ELISA) of NVs was also studied, and we observed thatboth V and CTX induce low levels of IL-1β (1.0 ± 0.4, 0.2 ± 0.1 pg/ml) but a proinflammatory effect can be observed with NVs +/- (12.5 ± 0.3, 12.4 ± 2.4 pg/ml).Thus, the results obtained in this work allow us to further refine the NVs for their possible use as adjuvants in the production of new generation AVs.